Airframe structural integrity in presence of corrosion is becoming an issue for ageing fleet. Fatigue damaging is effectively accelerated due to earlier crack initiation on corrosion damage. Reliability-based mechanical models of corrosion pit growth and fatigue crack growth associated with a pit to crack transition criterion and a failure criterion were set up and applied to the Alphajet aircraft corrosion-fatigue case. The probability distributions of the random variables and there correlations were determined through CEAT test database and the literature. This analysis reveals that a very high and negative correlation does exist between the Paris' law coefficients C_(eff) and m_(cr). Reliability in function of number of flights is computed for several corrosion severities. A reliability sensitivity analysis is carried out for a moderate corrosion. It appears that the reliability is relatively insensitive to the initial flaw size. Corrosion growth law, the rate of which is huge for small pit radius, explains the insensitivity to this random variable. A Risk Based Inspection approach in which the reliability is updated through the inspection is also proposed. When compared with the deterministic approach, the proposed approach, which realises a realistic treatment of the uncertainties, appears to provide with highly rich and interesting information profitable for the decision-maker. Concerning the maintenance, one reveals that in the study case, with the associated assumptions, the first inspection step calculated through deterministic approach is very conservative regarding the target reliability. Maintenance strategies such as delaying a 'heavy' inspection without loosing in reliability through the set up of intermediate 'light' inspections is assessed. In the study case, almost a three years delay is achieved.
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